Reptiles: Teacher’s Guide
Grade Level: 4-5
Curriculum Focus: Animals
Lesson Duration: Two or three class periods
Program Description
Cold-blooded, scaly, egg-laying (but not always). What else makes a reptile a reptile? Find out in
this eye-grabbing survey of snakes, crocodilians, and lizards. Snakes — No limbs? No problem!
See how snakes survive despite what we would consider a major handicap. Crocodilians — Learn
the biological secrets that have allowed these rapacious reptiles to persevere since the age of
dinosaurs. Lizards — Leaping lizards! Big or small, discover how they've adapted to four different
environments.
Onscreen Activities
Segment 1, Snakes
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Activity: Working in groups of three, create a Venn diagram that compares and contrasts
different reptiles. Your diagram might answer questions like, how are snakes different from
lizards? How are they the same? What’s the difference between a crocodile and an alligator?
What adaptations do they share?
Segment 2, Crocodilians
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Activity: Research an extinct reptile like the dinosaur, which died out 65 million years ago.
Describe the reptile’s adaptations, and speculate about why it became extinct.
Segment 3, Lizards
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Activity: Divide into groups of three and construct a model of a reptile. Use clay, play dough,
papier-mâché, or another material to make the model. Be sure it illustrates one or more of the
reptile’s physical adaptations.
Lesson Plan
Student Objectives
Students will understand:
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Adaptation describes the changing traits that enable reptiles to live in their environments.
Reptiles: Teacher’s Guide
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Adaptations can be found in physical and behavioral traits of reptiles.
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Snakes and lizards, turtles, crocodilians, and the tuatara constitute the living orders of reptiles.
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Materials
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Reptiles video and VCR, or DVD and DVD player
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Chalkboard or chart paper
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Marker
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Internet access
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Printer
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Research resources (e.g., Internet, CD-ROMs, encyclopedia, etc.) on reptiles
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Construction paper
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Pencil
Procedures
1. Share an amazing fact with students: At one time, giraffes came in a variety of neck lengths.
Some giraffes had much shorter necks than modern giraffes. Ask students to brainstorm why
short-necked giraffes did not survive. Then offer an explanation of natural selection:
The giraffes with shorter necks couldn’t compete with long-necked giraffes. Explain that
the giraffes were not in an actual contest that they could win by changing their physical
characteristics or behavior; they were unknowing participants in a competition that
takes place every day in nature: Food supplies are limited so animals must compete for
them with other species and like animals. Unlike the giraffes with long necks, shortnecked giraffes couldn’t reach leaves and twigs up high as well as the ones closer to the
ground. Because many animals could eat the low-lying vegetation, fewer short-necked
giraffes got enough to eat. Over generations, giraffes with longer necks grew stronger
and healthier. The long-necked giraffes had more and more babies that, like their
parents, inherited long necks and were better able to survive when food was scarce; no
other animal could reach the high leaves as well as they could. Over time, more and
more short-necked giraffes died before they could reproduce more short-necked babies.
Eventually, only long-necked giraffes were born. This process of change, called “natural
selection,” happens in all species.
2. Explain that a giraffe’s long neck is an adaptation, a trait that helps it fit in and survive in its
environment. Tell students that sometimes different species within the same family have very
different adaptations that depend on location. For example, the Siberian tiger has striped fur
while the snow leopard sports a white and black coat. These adaptations allow each species of
cat to meet the challenges of its different environment. The Siberian tiger’s striped fur keeps it
disguised in the dense forest of China; the snow leopard’s white fur helps it hide in its snowy
environment.
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Reptiles: Teacher’s Guide
3
3. On the chalkboard or chart paper make three columns. Label the first column “Animal,” the
second column “Adaptation,” and the third column “Effect.” Fill in the first two columns with
some sample animals and their adaptations. Then, ask students the effect of each animal’s
adaptation. Encourage students to add their own ideas to the list. Here are a few examples to
start the list:
Animal
Adaptation
Effect
Giraffe
Long neck
Can eat leaves in tall trees
(the parts of plants other
animals can’t reach)
Bird
Flies south in
winter
Warmth
Porcupine
Sharp, stiff
quills
Can defend itself against
enemies
Chipmunk
Hibernate
Can avoid winter food
shortages
Dolphin
Tail
Helps it swim
4. Point out the two types of adaptations: physical and behavioral. A polar bear’s thick fur, which
protects it from the cold, is an example of a physical adaptation. A lizard that “plays dead” to
avoid predators is displaying a behavioral adaptation. Invite students to review the adaptations
in their chart and identify each as either behavioral or physical.
5. Ask students to brainstorm about reptiles, noting their responses on the chalkboard. Add the
following traits to the list if the students haven’t already (or circle them if they’re already on the
list), explaining that these are definitive traits of all reptiles:
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Breathe through lungs
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Have an internal skeleton with a central backbone (vertebrate)
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Are cold-blooded (body temperature is directly related to its surroundings)
6. Explain to the class that reptiles have been living on Earth for over 300 million years. They’ve
been able to survive because of specific traits, both physical and behavioral, that enable them to
live in their environments. Then, introduce students to the following types of living reptiles
with these fun facts:
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Turtles spend most of their lives in the water and have plated shells covering their
bodies.
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Lizards have great vision and use their tongues to taste their surroundings.
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Crocodiles lose their teeth chomping on prey, but new sets always grow in.
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Snakes can go a long time without eating, but when they do, their meal is usually
another animal.
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Reptiles: Teacher’s Guide
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The tuatara is similar to a lizard, but the tuatara has a third eye and an extra row of
teeth.
7. Divide the class into groups of two or three students. Assign each group one of the following
reptiles to research: snapping turtle, rattlesnake, iguana, American alligator, chameleon, tuatara,
sea turtle, python, Nile crocodile. You could also let them select a different reptile of their own
choice.
8. Have students research their assigned reptiles using the resources you provide. To guide their
research, have them answer the following questions:
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What does your reptile look like?
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Where does it live?
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What does it eat?
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What are some adaptations? Name at least two, and explain how it helps the reptile
survive.
9. When groups complete their research, instruct them to make a diagram of their reptile with
labeled descriptions of the animal’s adaptations. Be sure they draw lines from the illustration to
each description. If necessary, show models of other types of diagrams. They should write any
behavioral adaptations underneath their diagram.
Discussion Questions
1. Reptiles have both physical and behavioral adaptations that help them survive in their habitats
over time. Name one physical adaptation and one behavioral adaptation from the reptiles you
studied.
2. The tuatara is the oldest living reptile. What types of adaptations have enabled this reptile to
outlive so many other reptiles?
3. Why do some consider dinosaurs the “original reptiles”? What traits do they share with other
reptiles?
4. Almost all reptiles have dry, scaly skin. Think about where most reptiles live, then brainstorm
some of the reasons for their skin characteristics.
5. Do a little research on crocodiles and alligators. Why are they both considered reptiles? How
are they different from each other?
6. All reptiles are cold-blooded; that is, their body temperature stays about the same as the
temperature of their surroundings. What adaptations do reptiles have, both behavioral and
physical, that help them survive as cold-blooded creatures?
Assessment
Use the following three-point rubric to evaluate students' work during this lesson.
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3 points: Student’s research report includes a thorough and well-written description of the
reptile including what it looks like, its preys, its predators, and a description of two or more
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Reptiles: Teacher’s Guide
5
adaptations and how they have helped the animal survive; the accompanying diagram is
labeled accurately and includes thorough descriptions of the reptile’s various features and
adaptations.
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2 points: Student’s research report is adequate and includes some description of the reptile and
an explanation of at least one of the animal’s adaptations; the diagram is partially labeled with
some description of the labeled parts.
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1 point: Student’s report shows little research, and descriptions are poorly written; no
adaptations are described, or they are described incorrectly; diagram is sketchy and does not
included labels with descriptions. You can ask students to contribute to the assessment rubric
by determining criteria for well-written research reports and diagrams.
Vocabulary
adaptation
Definition: Modification of an organism or its parts that makes it more fit for existence under the
conditions of its environment.
Context: The African lizard’s flat body is an adaptation that enables the reptile to fit into small
crevices when threatened by a predator.
cold-blooded
Definition: Having a body temperature close to that of the environment.
Context: The cold-blooded crocodile needs to sit in the sun to warm up.
reptile
Definition: Any of a group of cold-blooded, air-breathing vertebrates that usually lay eggs and
have skin covered with scales or bony plates.
Context: The reptiles, or class Reptilia, include turtles, crocodilians, the tuatara, and lizards and
snakes.
scale
Definition: Any of the small stiff flat plates that form an outer covering on the body of some
animals, especially fish and reptiles.
Context: Most reptiles are covered with horny scales or plates that protect their bodies from
drying out.
vertebrate
Definition: Having a spinal column.
Context: Reptiles are vertebrates; they have an internal skeleton with a central backbone.
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Reptiles: Teacher’s Guide
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Academic Standards
National Academy of Sciences
The National Science Education Standards provide guidelines for teaching science as well as a coherent
vision of what it means to be scientifically literate for students in grades K-12. To view the standards,
visit http://books.nap.edu.
This lesson plan addresses the following science standards:
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Life Science: Structure and function in living systems; diversity and adaptation of organisms
Mid-continent Research for Education and Learning (McREL)
McREL's Content Knowledge: A Compendium of Standards and Benchmarks for K-12 Education
addresses 14 content areas. To view the standards and benchmarks, visit http://www.mcrel.org/.
This lesson plan addresses the following national standards:
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Science: Understands how species depend on one another and on the environment for
survival.
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Science: Understands how species depend on one another and on the environment for
survival.
Published by Discovery Education. © 2005. All rights reserved.